Britain has one of the worst track records in hunting down and prosecuting suspected Nazi war criminals, according to a report by the Simon Wiesenthal Centre.

The centre says Britain has had only minimal success in dealing with the perpetrators of the Holocaust and it is urging the government to take urgent steps to improve the prosecution of suspected war criminals.

Britain fares badly in the centre's new table comparing the efforts of the 18 countries which are suspected of housing the most war criminals. Britain was placed in the "minimal success" category, with countries such as Argentina, Croatia and Costa Rica.

Scotland, which following devolution deals with its own extradition requests, fares worse than the rest of Britain. The report dismisses Scotland's efforts as "insufficient or unsuccessful".

The table, which the centre's Jerusalem-based Nazi hunting operation plans to publish annually, was yesterday described as unfair by a former British army Nazi hunter. Lord Janner, former MP and secretary of the all-party war crimes group, said the idea that it was possible to rank the Nazi-hunting efforts of countries was "ludicrous".

Efraim Zuroff, director of the centre's Jerusalem office, said: "At least we can try our hardest to ensure the perpetrators do not live out their lives in peace and tranquillity. We urge every government which faces this problem to maximise its efforts to ensure that as many as possible of the criminals are forced to pay for their crimes."

Lord Janner said: "This league table makes no distinction between commitment and results, nor does it take into account the circumstances of the country assessed both during the Nazi period and after."

Dr Zuroff's study points out that Britain has prosecuted no cases since the former Belarussian policeman Anton Sawoniuk, 79, was convicted of war crimes two years ago. The retired British Rail ticket inspector was given two life sentences.

Criticism of Scotland is based on its failure to prosecute Anton Gecas, a Lithuanian living in Edinburgh, who has been accused of the murder of up to 32,000 people.

The US was the only country to be graded "highly successful" in the first Nazi War Criminals Prosecution Status Report. It was the first country to use immigration and deportation procedures, rather than criminal procedures, to deal with war criminals and the Simon Wiesenthal Centre is keen for this method to be adopted globally.